To cope with the blooming information industry, various electronic products tend to introduce all kinds of integrated computer devices with different configurations to meet user's requirements. Since the general desktop computer, notebook computer, or standalone server has saturated data storage capacity and lacks expandability, the integrated design of external storage devices (such as redundant array of independent disk drives) becomes a key point for the research and development of the information industry.
Please refer to FIG. 1 for an illustrative diagram of the present external storage device, which has an integrated structure comprising several basic electronic modules such as an information storage unit, a power supply unit a logic and arithmetic unit, a heat dissipating unit, and a bus connecting unit. Compared with the general single storage device (such as a removable hard disk rack), the main point of consideration for the integration relies on the external storage device having an external power supply for the power and its application, and also having a heat dissipating unit to keep the internal storage device at a specific temperature and maintain the operating performance. However, the assembling of this kind of device still remains unchanged from the electric connection mode of a general computer system. Besides using a detachable connection mode to accomplish the convenience of a wireless connection, the data storage unit still needs a power cable or a bus cable for the connection between the arithmetic logic unit, the heat dissipating unit, and the bus connecting unit. First of all, such assembly not only involves long working hours and complicated manufacturing process, but also makes the maintenance or repair very difficult when the system or any component fails. The whole casing of the main system has to be removed first before the cable can be removed for maintenance and repair, and thus it is difficult to accomplish the hot-plug function.
Furthermore, since the cable is too long, a certain space must be reserved for accommodating the remaining cable when designing the computer casing. As a result, the overall volume of the device cannot be minimized to a size convenient for disposition or transportation, and definitely cannot comply with the trend of a compact product design. In addition, the isolation of the remaining cable will cause a poor performance on extracting the hot air produced by the interior heat generating units and directly affecting the operation and performance of the external storage device.